Not really playing ATM but, gods of war chains of olympus via PPSSPP on the phone seems to work well, probably give that a bash (most games are a bit poor via the touch screen controls, but top down ARPG style games seem to work alright).
Never alone: Ki Edition also looks grand for a bit of casual. Ready for text doctors visit or short trip.
On PC, I still haven't gotten around to the Pillars of Eternity 2 Deadfire expansions. Lord knows what I'll actually play next. It's like whether you crack a book or not.
On my windows tablet, it's either leo's fortune, or trine 2 usually, just for long distance travelling. I'd love to have a real RPG in touch mode for tablet, but alas, these never happen outside of the enhanced editions. I do have torment with the touch mode, and I never played that game far.